Have you put right tags when you posted today?
Do you use the most frequent and popular tags like "life", "steemit" or, "photography"?
Does you post have relations with your tags?
Do you use some tags that you "invented"? And do you think that you OWN those tags?
Is it possible to own the tag?
Is it necessary to protect your tag if others are violating it?

I see many tag-related-flags, tag misconceptions, tag abuses and even tag wars lately! People have very different opinions about tag usage so, let's discuss a bit about moral side of all.

As I already mentioned in a bunch of my previous posts, there are only few real rules about behavior on Steemit and those rules cover only one small part and the rest depends on moral and honesty of an individual.

If a decent and honest Steemer has #tags like # funny, # steemit and # life, that means that he just posted a funny post about Steemit or about something on Steemit with a touch of real life in it!
If the same Steemer posts some photos from a road trip, those #tags would be # photography and # travel, but # life is also allowed. But not # steemit!
If those photos were not taken on a road trip but on some Steem Meetup, you can add #tags # steemit and # steem, of course.

But many people, including me on my beginnings, tagged all as #steemit until we weren't flagged for that. And that's fair!

This is the reason:

If you use a formal tag but your post doesn't have anything with a topic f that tag, that means that you spread false information! And you deserved that flag!

But what with not so popular tags that individual Steemers invented for themselves and their actions?

I have my own tag, #whysoserious. First I used it for not-serious posts, but it came up that each of my posts had something funny in it, so, #whysoserious became my main tag! And I want others to use it! No rules! Just don't be dead-serious when you use it!
My Steemit friend @bullionstackers came out with tag #whalepower, he needs that tag for his #whalepower curation system and has certain rules if you want to use that tag.
Those are not elementary tags like #steemit and if you want to protect them, you should make some rules but avoid to defend your own tag with flags.
Tags cause misunderstandings and disagreements on Steemit, so we have our # memechallenge by @fibra59 and new # memecontest by @gonzo. And many people who wanted to participate on memecontest tagged their posts as # memechallenge. But that tag was originally invented by @fibra59 for needs of his memechallenge. So he decided to defend that tag with flags (but in most decent way, with warnings). Since that tag has never been used before @fibra59 and his memechallenge made something great on Steemit, my personal opinion is that actions of @fibra59 are justified!

So, the question from the title:

Can somebody OWN the tag?

I'll give you my personal opinion but I wish to see yours opinions down in the comments!

If you use some standard and well known #tags, then your post should be right about that topic. Nobody owns that tag, but if you abuse it, many users will flag you! We have pretty active @steemcleaners who will notice very quickly if you abuse tags like # steemit or # introduceyourself.
If you use some tags that other users invented, first check what are those #tags about! Nobody owns that tag, but if someone didn't make some rules about it, feel free to use it!